Folding machine



0t.23,1956 J, W- MAY E-rAL 2,767,980

FOLDING MACHINE 'Filed July 12. 1952 s sheets-sheet 1 A 1* Si E Q S, 2V cm2 1 y l I NORMANv E. KLEIN WM@ QM ATTORNEY Oct. 23, -1956 J. w. MAY Erm.

FOLDING MACHINE 3 Sheets-Sheet 2 Filed July 12, 195,2

INVENTORS. JOHN W. MAY

NORMAN E. KLEM am 5M ATTQRNEY Oct. 23, 1956 J. w. MAY ETAL 2,767,980

FOLDING MACHINE Filed July l2., 1952 3 Sl'leets-SheecA 3 INVENTORS. doHN W MAY BY NORMAN E. KLEIN MKM ATTORNEY United States Patent O FLDNG MACHINE John W. May, Wynnewood, Pa., and Norman E. Klein, Pendleton, S. C., assignors, by mestre assignments, to Deering Milliken Research Corporation, near Pendleton, S. C., a corporation of Delaware Application July 12, 1952, Serial No. 298,604

1% Claims. (Cl. 270-94) This invention relates to improvements in folding machines and, more particularly, to machines for longitudinally folding a strip or web of cloth or fabric.

In the manufacture of preformed diapers of the gauze type, it is customary to cut the material into lengths suitable for the article and then hand-fold each piece thus cut, longitudinally a number of times to obtain the desired width and thickness. The material thus folded may then be stitched along its opposed marginal edges to retain the folds in place.

It has been determined that a diaper thus formed has the disadvantage of being bulky and causing some discomfort to the infant. To overcome these disadvantages and also elect an economy in material, an improved diaper has been devised which is formed of a single piece of material double-folded in such manner as to provide but two layers or plies of cloth along the marginal edges and four plies intermediate the marginal portions. The folding is also preferably accomplished in such manner that the two selvage edges are brought together in matching relationship and define one outer edge of the intermediate four-ply section. Stitching, in this instance, is directed only along each of the edges of the four-ply section, thereby leaving the twoply marginal sections extremely eXible and free from construction which would otherwise tend to irritate the legs of the infant.

The performance of the last described folding operation by hand is tedious, time consuming and costly. It is, therefore, a principal object of our invention to provide a machine for continuously and automatically folding a strip or web of material longitudinally to provide a product having a lesser number of plies along its marginal edges than throughout the portion intermediate the marginal portions.

A further object of our invention is to provide a machine for continuously producing a plurality of longitudinal folds in a strip of cloth, which machine is simple in construction and operation and, above all, economical to manufacture.

A specific object of our invention is to provide a novel means for matching the selvage edges and maintaining these edges in alignment during the continuous folding process of a web of cloth wherein an improved multi-ply product is achieved.

Other objects and advantages relate to the structural arrangement of the folding machine and will become apparent as the description thereof proceeds.

In general, the machine of our invention provides for the mounting thereon in a horizontal position of a rolled web of cloth of desired Width. As the web is rolled off, it is directed under guide rods terminating in a guide plate and, simultaneously, has its opposed selvage edges brought upwardly around the rods and towards each other into contacting matching engagement. The matchingV selvages are held in contact by suitable mechanism as the web is drawn through the machine. Other folding 2,767,980 Fatented Oct. 23, 1956 means, in the form of guide rods also terminating in a guide plate, deflect the once folded web to produce a second fold. The second folding means causes the web to be drawn snugly about the lirst guide plate and coacts with the selvage gripping device to complete the fold. The second folding means are so disposed that the double fold occurs above the first guide plate and laterally displaced inwardly from one marginal edge thereof. In like manner, the selvage gripping device is aligned laterally inwardly from the other marginal edge of the rst guide plate so that, when the web is released from the selvage gripping means, the completely folded web will have marginal portions of double ply and a portion intermediate the marginal portions of four-ply cloth.

The invention is more specifically described hereinafter in connection with the accompanying drawings, in which:

Figure l is a perspective view of the folding machine of our invention;

Figure 2 is an enlarged perspective view of one of the web guiding means of the folding machine;

Figure 3 is an enlarged perspective View of the selvage matching device forming a part of the folding machine;

Figure 4 is a fragmentary plan View of a section of the folding machine;

Figures 4-A, 4-B and 4-C are fragmentary sectional views taken respectively through lines A-A, B-B and C-C of Figure 4 and illustrate three different stages of web folding operation.

Figure 5 is an enlarged perspective View of a modified form of selvage matching device embodied in the folding machine; and

Figure 6 is an enlarged View partially in section of the feeler orifice member embodied in the device shown in Figure 5.

In Figure 1, the reference numeral l@ designates a platform supported by a plurality of legs il and an end frame 12. The end frame l2 carries a pair of horizontally extending brackets 14, only one of which is shown, for rotatably supporting a cloth roll i6 on which is wound the web i8 to be folded. The web i8 is adapted to be unrolled and fed into the machine about a series of guide rolls 2), 22 and 24?. rotatably mounted on the end frame l2, as shown. The web l@ is rst passed about the roll 2li upwardly and over the top of roll 22, downwardly under the roll 24 and then proceeds in a direction inclined with but toward the platform 10.

A frame 26 rises vertically from the platform 10 and has a pair of horizontal support arms 2S and 29 adjacent the upper end thereof. The arms 2S and 29 provide support means for a cloth guide 3? of generally elliptical shape, about which the web iti is adapted to be drawn as it leaves the lower side of guide roll 24. The cloth guide Sti is preferably formed of round rod stock and is mounted for adjustment laterally of the web, as more clearly snown in Figure 2. More specifically, the guide 36 has its ends suitably secured to a pair of plate members 3l and 32. These members are rigidly held in spaced relation with respect to each other by a pair of rods 34. The plate members 3l and 32 are, in turn, mounted for sliding movement along rods 36 and 37, the ends of which are rigidly secured between the support arms 28 and 29. Lateral traverse of the plate members 3l and 32 is accomplished by means of a threaded rod 46 having threadwise engagement with an internally threaded sleeve 3S secured to the late member 3l. The outer end of the threaded rod 4@ is journaled in the arm 23 and has a pair of flanged collars i2 suitably secured thereto, only one of which is shown, thereby enabling the rod 40 to be rotated without longitudinal movement with respect to the support arm 28. The extreme outer end of the rod 46 has a reduced square portion 44 to enable the application of a suitable tool, such as a wrench or crank, in the event it is desired to rotate the rod 40 to effect lateral adjustment of the guide member 30.

As the web 18 leaves the guide member 30, it is directed toward and through a selvage matching device, generally indicated at 46, which will be more specifically described hereinafter. From the selvage matching device 46 the opposed selvage edges of the web 18 are brought together and fed into a selvage gripping and advancing arrangement. This arrangement comprises a pin tenter belt 48 operative about a grooved drive pulley E@ and an idler pulley 52.

The drive pulley Sti is mounted on a shaft 54 for rotation therewith in a generally vertical plane. The shaft 54 is journaled, preferably at its ends, in upright supports 56 and 57 carried by the platform 1G. The idler pulley 52 is mounted for rotation in a transverse plane slightly inclined with respect to the horizontal, as shown, and is carried by one end of a bell crank 58 pivotally mounted at 60 to a plate 62 secured to one end of an arm 64. The free end 66 of bell crank SS carries a threaded screw 68 provided with the usual lock nut arrangement and is adapted to bear against the side of arm 64. Thus, by loosening the lock nut and screwing the screw 68 inwardly, that is, in a direction toward the arm 64, the bell crank 58 will be rotated in a clockwise direction about its pivotal support 60, as viewed in Figure 4, to increase the tension in the belt 48. Conversely, rotating the adjusting screw 68 in the opposite direction will permit bell crank 58 to rotate in a counterclockwise direction to relieve the tension on the belt 48.

The other end of the arm 64 is pivotally secured to a U-shaped bracket 7i) mounted on the platform 10, thus enabling the arm and the idler pulley assembly to be rotated about the pivotal support at the bracket 7i). The idler pulley assembly, however, is adapted to be held in an adjusted position, and to this end the arm 64 adjacent the plate 62 is adjustably held in clamping engagement with an upstanding angle bracket 72 suitably mounted on the platform 1d. The bracket 72 has an arcuate slot 74 therein for the reception of a clamping bolt 76 passing through the arm 64. Thus, by loosening the bolt 76, the idler pulley assembly carrying the tenter belt 48 may be moved up and down within limits of the arcuate slot 74 so as to bring the pulley assembly into alignment with the selvage matching device 46.

The plate 62 carried by the arm 64 has a pair of U- shaped brackets 78 extending upwardly therefrom and transversely across the idler pulley 52 and are joined at their outer ends by a bridging bar 80. The bridging bar 30 supports one end of a belt guide rail 82, the other end of which is secured to a support bar 84 mounted for rotation on a bearing block 86 suitably secured to the platform adjacent to but offset with respect to the drive pulley 50.

The belt guide rail 82, as more closely shown in Figures 4-A and 4-B, comprises a metal back-up strip 88 and a grooved guide strip 90, preferably of hard fiber, plastic or other suitable material. The groove in the strip 90, as more clearly shown in Figure 4-B, provides a channel into which the pins on the tenter belt 48 may ride. It will be noted, as shown in Figures 4-A and 4-B, that the metal back-up strip 88 and its grooved guide strip undergo a deformation throughout its length from the idler pulley S2 to the drive pulley 5d, namely by having placed therein a torsional displacement of its face amounting to approximately a 90 twist. The torsional displacement of approximately 90 is devised so that the guide rail 82 will follow the twisted contour of the belt 48 in its travel from the idler pulley 52 to the drive pulley Si).

A plurality of back-up rollers g2, in this instance five, are suitably mounted on angle brackets 94 carried by the back-up strip 83 in order to maintain the pin tenter belt 48 closely adjacent to the grooved guide strip 90. Thus, the matched selvages leaving the matching device 46 are caused to be drawn between the tenter belt 48 and the grooved guide strip as the belt is driven in a direction to cause counterclockwise rotation of the idler pulley 52, as viewed in Figure 4.

As the web 18 is advanced around the elliptical guide 3d, it is directed under and about a pair of guide rods 96, each supported at one end from the lower end of a channel member 98 carried by the frame 26. The rods 96 are inclined toward the platform 1t) and extend under the driven shaft 54, terminating a short distance therebeyond. To the ends of the rods 96 is secured a guide or folding plate 16), which plate is provided with a cutout portion 102 adjacent one edge thereof to provide clearance for the pins of the tenter belt 48 as the latter passes over the drive pulley 50. At the point where the web 18 engages the tenter belt 48, as shown in Figure 4-A, the web is looped completely but loosely around the guide rods 96 having its selvage edges engaged by the pins of the tenter belt. As the looped web 18 advances, the left-hand portion above the left-hand guide rod 96, as viewed in Figure 4-B, engages a deflecting guide rod 104, one end of which is supported by a vertical pedestal 106 rising from the platform 10 and positioned to one side of the path of travel of the looped web. The guide rod 104 is preferably curved and projects laterally inwardly toward the opposite side of the path of travel of the web and terminates coextensively with the right-hand edge, as viewed in Figure 4, of a second folding plate 108. The lefthand edge of plate 103, as shown in Figure 4, is attached to a curved support arm 110 mounted in an adjustable bearing block 112 attached to the platform 10.

With particular reference to Figures 4-B and 4-C, it will be apparent that as the looped web 18 advances toward the driven shaft 54 a second feld begins to form due to the deective action of the deflecting rod 104. The maximum amount of deflection is reached when the web passes over the second folding plate 10S, as more clearly shown in Figure 4-C. It will also be observed from the illustration shown in Figures 4-A to 4-C, inclusive, that the slack in the web 18 is gradually being taken up so that, when the web emerges from and is released by the tenter belt 48, the web will be snugly drawn about the folding plate 10). The right-hand edge of the second folding plate 108 is displaced inwardly to the left of the right-hand marginal edge of plate 100 by an amount to produce the desired right-hand marginal edge of twoply thickness. Similarly, the tenter belt drive pulley 50 is positioned on shaft 54 in such manner that it is displaced inwardly to the right of the left-hand marginal edge of guide plate 106 to provide a marginal band along the left-hand side of the folded web of desired width, also having two-ply thickness. It will, of course, be apparent that the portion intermediate the two marginal bands Will have a four-ply thickness.

A generally U-shaped guide 114, supported at its ends by the arm 64, extends laterally inwardly to the left, as viewed in Figure 4, to assist in maintaining a smooth contour of the web during the folding process. The folded web, as it emerges from the influence of the tenter belt 48, is grasped between a pair of rollers 116 and 118, either of which or both may be driven by suitable power means. As shown in Figure l, only roller 116, the periphery of which may be provided with a burred or roughened surface, is adapted to be driven by a sprocket 120 is driving engagement with a chain 122. The chain 122 is driven from a sprocket 124 secured to the end of a Shaft 126, in turn driven by an electric motor 128. Roller 118 is, preferably, covered with resilient or pliable material, such as sponge rubber, and is mounted in a pair of pressureregulating arms 13? and 137., one of the ends of each is pivotally supported from the platform 10. The opposite ends of the arms 13) and 132 have appertures therethrough for the reception of a threaded bolt 134 having its lower end anchored in any suitable manner in the platform 19. A coiled spring 136, disposed between each oil-thel arms 130 and 132, and suitable fastening means, suchas a wing nut 13S, yieldingly urges the roller 118'toward the roller 116. The pliable coating on the roller 118 provides improved gripping action of the drive roller 118 in spite of the fact that the web 18 is composed of dilferent thicknesses or plies of material when it passes between the rollers.

The chain 122 also passes over an idler sprocket 140 and,V in turn, engages a sprocket 1112 secured to the end of shaft S4. T he sizes of the roller 116, drive pulley S and the two'sprockets 121i and 142 are so selected that thesurface speed of the roller 116 is equal to that of the tenter belted; lt is, thus, clear that as the web is advancedthrough the machine by the action of the rollers 116` and 118the matched selvages of the web are advanced atthe same rate.

The folded web, upon leaving the dnive rolls 116 and 118, may be cut transversely in suitable lengths, if desired, ormay be rolled up on af'suitablel take-up device 144 driven in conventional manner not shown. It is also conceivable that, prior to being rolled or cut in suit-able lengths, the folded web may be stitched'longitudinally along the marginal'edges of the intermediate lfour-ply section.

In `order to enable the folding process to proceed at high speed, it is necessary to provide mean-s, suchV as the device generally indicated at do, for automatically align-ing the selvages of the web as these selvages are fed'into gripping` engagement with the pin ten-ter belt 415. Such selvage matching device is more clearly shown in Figure 3. The elliptical guide 36 is formed and proportioned to .assist in bringing the opposed selvages of the web 18 together. F llo-wing engagement with the gu-ide 3i), the two selvages respectively engage the opposed faces of a pair of relatively closely spaced pin wheels 15d and 151. Each pin wheel is mounted for rota-tion in anti-friction bearings journaled in the opposite end of a bifurcated arm 152 having a shaft 154 extending from the closed end thereof.'

The shafts 154 are respectively journaled adjacent one end of each of two parallel channel members 156 and 157, thereby enabling the pin wheels 150 and 151 to swivel about an axis at right angles to their planes of rotation.` The other ends of the channel members 156 and 157, are preferablyv joined by a bridging platte 158 which, inturn, is mounted adjacent the lower end of support member 98a 1t will, thus, be seen that the` position the respective selvageedges of the web 18 maintain with respect to their corresponding pin wheels against which the selvages are drawn will depend upon the position setting of the bifurcated arms 152. In order to maintain the top edge of the selvage that is in contact with the pin wheel 151i at the proper level, it is necessary that the pin Wheel rotate in a plane generally parallel with the top edge of the selvage. Shouldthe top edge be running low or in danger ofv being dropped by the pin wheel, a given rotation ofthe arm 152 about the axis of shaft 154 in a clockwise direction, as viewed in Figure 3, will be necess-ary toeffect normal operation. Similarly, if such selvage has a tendencyto run high, rotation of the arm 152 in a counterclockwise direction will be required to res-tore normal conditions.

ln order to cause the pin wheels 151i and 151'to automatically regulatethe level at which the two selvage edges are brought into Contact, we have provided a pair of sensingrmembers 160 and 161, each having a relatively long tapering arm curved downwardly at the narrow end and terminating in a saddle-like feeler 162 adapted to ride astride a respective selvage edge. The opposite end of each sensing member 166 and 161 has a shaft 164 rigidly secured thereto journaled for rotation in antifriction bearings mounted respectively in the channel members 156 and 157. The sensing members 16@ and 161 also include re- 6 spective upstanding arms 166 and 167, preferably formed .integrally therewith.

The arms 166 and 167 have a number of openings therethrough for attaching at the selected opening a swivel block 168. The blocks 16S have an opening therethrough for the reception of the threaded end of a coupling rod 170 and are each fur-ther provided with a cap-tive knurled thumb nut 171 making threadw-ise engagement with the rod. The other end of each rod 17) is pivotally joined to a clevis block 172. Each clevis block is adjustably mounted as by means of a set screw 173 to a rod 174, one end of which is suitably secured to a respective bifurcated arm 152. The rods 174 are so set in the arm 152 that oscillation thereof in a plane perpendicular to the shaft 154 will rotate each arm 152 about its axis.

The extent of circumferential engagement of the selvage` with the pin wheel 15@ is determined by two guide rods 176 and 177 respectively positioned on the leading and trailing sides of the pin wheel. The rod-s 176 and 177 are adjustably supported by a bridging bar 180 extending across Athe channel members 156 and 1.57 and may be secured thereto in any suitable manner, such as by bolts, as shown.

A second set of guide rods 17; and 179 is similarly mounted on the bridging oar 131i and serves a like function with respect to pin wheel 151. Generally, it may be said that therods 176 and 177 are right-handed and the rods 178 and 179`are left-handed, `as viewed in Figure 3.

In oper-ation,- the device 46 automatically matches the two selvage edges as follows: it is assumed that the various linkages-coupling the feeler 162 with the pin wheel support arm 152 have been adjusted tor normal operation and a condition ensues under which the salvage edge of the web18 being drawn across the surface of the pin wheel is Vrunning too high. if t-he salvage is too high, feeler 162 will be raised, causing the sensing member ad and its arm 166 to be rotated in a clockwise direction about the axis of shaft 164. Motion is thus transmitted through rod 17) to rod 174 causing pin wheel 150 to be rotated about the axis of shaft 154 in a counter-clockwise direction. Such change in the position of the plane in which pin wheel 150 is caused to rotate will in turn cause the selvage edge to migrate downward and assume a position as controlled by the position of the feeler 16.2. lt will be observed thatin the event the selva-ge is running too lov,l feeler 162 will follow the selvage edge to cause swivel-ing action of the pin wheel about the axis of shaft 154 in a clockwise direction. This change in plane of rotation of the pin wheel 150 causes the pin wheel to assume a course inwardly from the edge of the web creating a reaction that will cause the selvage to be rai-sed with respect to the pin wheel. 1t will also be observed that a particular selvage control position may be preselected, within certain limits, by adjusting the position of the captive knnricd nut 171. Turning the nut 171 in a direction to shorten the rod 171i` will cause the selvage edge to be lowered with respect to the pin wheel 151); conversely, turning the thumb nut in the opposite direction to eifect a lengthening of the coupling rod 170 will effect a raising of the selvage with respect to the pin wheel 15d. The operation and regulation of the selvage control device for the pin wheel 151-is identical to that previously described for pin wheel 150. The sensitivity of the regulating dev-ice is capable of being adjusted further in that the levers 166 and 167 have three positions in which the swivel blocks 16S may be mounted to change the mechanical advantage as is deemed necessary. in like manner, the lever arm may be changed with respect to the position of the swivel blocks 172 on the arms 174, creating further range of sensitivity adjustment. The provision of the set screw 173 in the` swivel block 174 permits tine adjustment of the block with respect to the axis of rotation of shaft 15d.

In order that the feeler 162 will accurately follow the selvageedge, it is desirable to provide a slight bia-sing force in the direction toward the selvage edge. It has been found that the combined weight of the feeler 162 and member 160 or 161, as the case may be, provides a greater biasing force than is needed. To counteract the excessive biasing force, the arms 166 and 167 are each provided with a rod 182 projecting beyond the axis of rotation of the members 160 and 161. To the rods 182 may be secured, as by set screws, a mass in the form of collar 184 to serve as a counterweight. By slidably adjusting the collars 184 toward or away from their respective arms, the desired compensation can be achieved. It will, of course, be understood that complete compensation is not desired inasmuch as sufficient bias by gravity is necessary to cause the feelers 162 to accurately follow the top edge of each selvage.

It will also be apparent to those skilled in the art that the proper biasing force for causing the feeler 162 to follow its respective selvage edge may be obtained by spring means. In such instance the feeler and its coacting member 160 are not limited to a mounting position for tracking the edge of material traveling in predominately vertical planes but will be operative to track material traveling in subsantially horizontal planes as well.

In Figure 5, an alternate arrangement is shown for automatically controlling the angle of tilt of the pin wheels 150 and 151 which, in turn, align the two selvage edges of the web being folded. Throughout the description of this alternate arrangement, identical parts heretofore described will be given the same numerals of reference.

In this instance, the bifurcated arm 152 is rocked about the axis of shaft 154 by the action of bellows 190. The bellows 190, preferably, is of the Sylphon type, having end plates 192 and 194. End plate 192 may be attached to the upstanding portion of an angular bracket 196, in turn supported from the bridging bar 180. The end plate 194 is free to move as the bellows is expanded or contracted, and is provided with a connecting rod 198 coupled to a clevis block 200 adjustably mounted on an operating rod 202, the lower end of which is fastened to the arm 152.

End plate 192 is provided with an opening therethrough to receive and have sealed thereto a rigid section of tubing 204 adapted to make connection with a vacuum pump, not shown, through a hand controlled valve 205. A second section of tubing 206 is joined at one end to the tubing 204 and supports at its other end an orifice feeler member 208. As more clearly shown in Figure 6, the feeler member 208 has a bore 210 therein communicating at its upper end with the tubular section 206 and has its lower end closed by a cap member 212. A slot 214, of diametrical cut, extends upwardly through the cap member 212 and terminates adjacent the upper end of the feeler to provide an orifice for the admission of air. The slot 214 is of width substantially equal to the thickness of the selvage so as to enable the selvage to be drawn therethrough. The cap member 212 may have the portions on either side of the slot 214 rounded, as shown at 216, to facilitate threading the selvage edge therein. It will, thus, be apparent that the position of the selvage in the slot 214 will determine the effective orifice area and, consequently, effect the pressure conditions in the bellows 190.

A spring 218, having one end connected to the clevis block 200 and the other end attached to a threaded rod 219 slidably secured to a projecting tab 220 on the arm 156, tends to maintain the bellows 190 in extended condition, A knurled thumb nut 221 making threaded engagement with the rod 219 provides a suitable means for adjusting the tension of spring 218.

in operation, the selvage edge of the web 18 is placed on the pin wheel 150 and fed through the slot 214 of the feeier 208. Valve 205 is adjusted so that the proper vacuum is drawn within the bellows 190, causing the desii-ed position of end plate 194 and, consequently, the proper setting of the pin wheel 150. For normal operation, it is desirable that the feeler member 208 be positioned so that the selvage edge of the web 18 occupies about one-half the length of the slot 214.

In the event the selvage has a tendency to run ltoo high, more of the slot 214 will be closed off to atmosphere, thereby causing the pressure in bellows 190 to be lowered with a consequent movement of its end plate 194 to the left. Such movement of the end plate 194 actuates the rod 202 to rotate the bifurcated arm 152 in a counterclockwise direction with the result that the plane of rotation of pin wheel will be changed with respect to the edge of the web to cause the pin wheel to take less lateral bite into the selvage. As the level of the selvage is being lowered, more and more area of the slot 214 is again exposed, causing a greater amount of air to flow into the bellows to raise the pressure therein and permit spring 218 to arrest the counterclockwise motion of rod 202 and even reverse the movement of rod 202 to cause rotation in a clockwise direction until stable conditions are reached. In the event the selvage has a tendency to run too low, the feeler member 208 allows a greater amount of air to be drawn into the vacuum system with a resultant rise in pressure in the bellows 190. As heretofore stated, an increase in pressure in the bellows will result in a clockwise rotation of arm 152 to enable the pin wheel 150 to take a greater bite laterally into the selvage, causing the selvage level to rise in the slot 214 until normal conditions are restored, as heretofore described.

It will, thus, be apparent that with a given feeler orifice and the adjustment of the opening of valve 205 and the tension of spring 218, the system is made to regulate the selvage level at the desired position. It will, also, be apparent that an identical vacuum-operated bellows arrangement can be provided for controlling the position of pin wheel 151 and also provided for its regulation so that the two selvage edges are brought into tracking alignment as they enter into engagement with the tenter belt 48.

While we have disclosed the arrangement of Figure 5 as being operative by vacuum, it will be readily understood by those skilled in the art that such system will also effectively operate by air pressure above atmospheric, in which case suitable mechanical linkage for reversing the direction of movement of component parts from that heretofore described are required. It is also to be understood that, while we have shown and described a folding machine for longitudinally folding a web of cloth or fabric, the same is merely for the purpose of illustration and that the principles of the machine are applicable for folding flexible material generally, and that changes and modifications can be made by those skilled in the art Without departing from the spirit and scope of the appended claims.

The following is claimed:

l. A machine for longitudinally folding a web of material comprising means for initially guiding the outer longitudinal edges of the web into juxtaposition, means for holding said edges in said position during the folding operation, a second guide means about which said web is adapted to be drawn to provide a first fold of predetermined width, a third guide means coacting with said holding means and said second guide means and against which the singly folded web is drawn, said third guide means being arranged to form a double fold extending transversely over at least a portion of the width of said singly folded web, and means for continually advancing said web through the machine.

2. A folding machine according to claim l wherein the first-named means comprises a generally elliptically shaped member, the plane of which is positioned substantially normal to the direction of travel of the web and about which the web is adapted to be drawn followed by a pair of spaced guide members for directing the outer marginal edges of the web toward each other.

3. A folding machine according to claim 2 wherein the pair of guide members are movable to bring the two opposed marginal edges into alignment, and means for automatically moving said guide members in response to 9 misalignment of said edges to maintain proper alignment.

4. A folding machine according to claim 1 wherein the means for holding the edges of the web in juxtaposition during the folding operation are at least in part movable with said edges.

5. A folding machine according to claim 1 wherein the means for holding the edges of the web in juxtaposition during the folding operation comprise a stationary backup rail member and a coacting pin tenter belt, at least one reach of which is caused to move closely adjacent said rail member and advance the edges of the web longitudinally therebetween.

6. A folding machine according to claim 5 wherein the tenter belt operates about a driven pulley and an idler pulley, said pulleys being mounted for rotation in planes displaced by substantially 90 from each other, the idler pulley being disposed at the web-receiving end of the reach and the driven pulley being disposed at the webdischarge end of the reach of said belt, the continuous transition of said belt from one plane of operation to the other assisting in completing the folding operation.

7. A folding machine according to claim l wherein the second guide means comprises a plate supported from the ends of a pair of guide rods and about which the web is drawn, the width of said plate determining the width of the folded web.

S. A folding machine according to claim 1 wherein the third guide means comprises a second plate supported from the end of curved guide rods disposed above said second guide means and having an outer marginal edge displaced transversely inwardly from one edge of said second guide means to define the position of the double longitudinal fold.

9. A folding machine according to claim 1 wherein the means for advancing the web through the machine comprises a pair of rolls yieldingly biased toward each other and between which the folded web is adapted to pass, and means for driving at least one of said rolls.

10. In a machine for longitudinally folding a continuously moving web of material, means maintaining the transverse elements of said web in a substantially horizontal plane during movement thereof into said machine, means directing the marginal edges of said web upwardly and toward each other, means for moving said edges in vertical planes relative to each other to bring them into alignment, and means for directing said aligned edges into contact with each other to thereby form said web into a tube, guide means operatively positioned within said tube to distend the corresponding transverse portion of said tube horizontally to either side of said edges while said edges are in contact with each other, and means for advancing said edges through the machine at the same rate as the remaining portions of the web.

ll. In a machine for longitudinally folding a continuously moving web of material, means directing the marginal edges of said web toward each other, means for aligning said edges relative to each other and means for directing said aligned edges into contact with each other, said means for aligning the marginal edges of the web including at least one pin wheel the periphery of which engages one of said edges, said pin wheel being mounted for swiveling movement about an axis at right angles to its aXis of rotation whereby the angle between the plane in which the wheel is rotated and the direction of travel of said edge may be varied to effect a change in position the edge, and means for automatically controlling said swiveling movement to maintain said one edge in alignment with the other of said edges.

12. The folding machine in accordance with claim 11 wherein said last-named means comprises a sensing feeler in engagement with said one edge of the web and a lever linkage coupling said feeler to said pin wheel mount whereby changes in the position of said one edge are transmitted to said pin wheel mount to cause the pin wheel to eiect compensating changes in the position of said one edge of the web.

13. In a machine for longitudinally folding a continuously moving web of material, means directing the marginal edges of said web toward each other, means for aligning said edges relative to each other and means for directing said aligned edges into contact with each other, said means for aligning the marginal edges of the web including a pair of pin wheels, the periphery of each wheel engaging a respective edge, means mounting said pin wheels in spaced relation and for swiveling movement about an axis at right angles to their respective axes rotation whereby the respective angles of the planes in which each wheel is rotated may be varied with respect to the angles of travel of each respective edge to effect a change in position of each of said edges, and means for independently controlling the swivel movement of each of said pin wheel mounts to maintain said edges in alignment.

14. The folding machine of claim 13 wherein said last-named means comprises a pair of sensing ngers, one in engagement with each of said edges and linkage means operatively coupling each of said feelers to its respective pin wheel mount, whereby changes in the position of said edges are transmitted respectively to said pin wheel mounts to effect compensating changes in position of the edges of the web.

l5. A folding machine according to claim 18 wherein said means for directing said aligned edges into contact with each other and said means for advancing said edges comprise pin tenter belt and a back-up support extending along one reach of said belt and between which said edges are held against relative movement as the web is advanced through said machine.

16. A machine for longitudinally folding a continuously moving web of material comprising a horizontal platform, a pair of guide rods each having one end supported above said platform and inclined downwardly toward said platform, a guide plate carried by the free ends of said rods and terminating closely adjacent to said platform, means directing said web over said guide rods and deflecting the marginal edges thereof upwardly around said rods, means for continually directing said marginal edges into contacting matching engagement with each other to provide a single fold, a curved guide rod having one end supported from said platform and extending laterally inwardly into the path of movement of said singly folded web, a second guide plate supported from the free end of said curved guide rod having one marginal edge coextensive with said curved rod and its end terminating above and closely adjacent said first guide plate, said curved rod and second guide plate deilecting said singly folded web to position and form a second fold to produce a double fold, said means for continually directing said marginal edges into contacting matching engagement being inclined downwardly toward said platform and releasing said marginal edges above and closely adjacent to said first and second guide plates to complete the fold.

17. The folding machine in accordance with claim 11 wherein said last-named means comprises pneumatically operable means for changing the position of said pin wheel and an orice member in contact with said one edge of the web and arranged to control pressure conditions in said pneumatic means in accordance with the position of said one edge of the web to cause compensating changes in the position thereof.

18. In a machine for longitudinally folding a continuously moving web of material, means maintaining the transverse elements of said web in a rst plane during movement thereof into said machine, means directing the marginal edges of said web toward each other, means for moving said edges in second and third planes transverse to said first plane and relative to each other to bring them into alignment, and means for directing said aligned edges into contact with each other to thereby form said web into a tube, guide means operatively positioned within said tube to distend said tube along said 11 12 first plane to either side of said edges while said edges References Cited in the le of this patent are held in contact with each other whereby said edges UNITED STATES PATENTS are joined intermediate the sides of said distended tube,

and means for advancing said edges through the machine 569'917 Goss Oct' 20 1896 at the same rate as the remaining portions of the web. 5 1085537 Burgess et al Jan' 27 1914 1,143,801 Bates June 22, 1915 1,480,017 Sewall Jan. 8, 1924 1,857,735 Monforts etal May 10, 1932 

